Catfish With Tomatillo Salsa In Packets

Name: Catfish With Tomatillo Salsa In Packets
Ingredients: 1 pound tomatillos, (see Tip), husks removed, coarsely chopped; 1-1 1/4 pounds catfish, cut into 4 portions, or 4 tilapia fillets (4-5 ounces each); Juice of 1 lime; 3/4 teaspoon salt, divided; 1 medium onion, finely chopped; 1/2 teaspoon freshly ground pepper; 1/3 cup chopped fresh cilantro; 3/4 teaspoon ground cumin; 2 cloves garlic, minced; 1 jalapeño, or serrano pepper, minced; 1/4-1/2 teaspoon cayenne pepper, (optional); 1 tablespoon extra-virgin olive oil